It looks like Familysearch just added Texas County Tax Roll records yesterday as well. They look very good but as of today they are "Browse Only". Hopefully they'll add the ability to search them soon. I randomly chose Walker County in 1880. I found the following info for Rev. G.B. Orviss :

Owner: Orviss G.B.
Land Abstract No. : 86
Certificate No.:
Survey No.
Original Grantee: R.L. Brooks
Acres: 60
Value: 100
City/Town:
No. of Lot:
No. of Block:
Value :
No. Certificates:
Total Amount in acres:
Value:
Carriages/Buggies/Wagons No. : 2
Carriages/Buggies/Wagons Value : 70
Horses and Mules No. : 3
Horses and Mules Value : 90
Cattle No. : 38
Cattle Value : 180
Hogs No. : 15
Hogs Value : 15
.
.
.

I also saw records for Joshua Houston Sr and Jr. and Samuel Walker Houston all in Huntsville. Some rather well known African American Texans.

Ron